newsupernova/vendor/magento/module-sales/Block/Adminhtml/Order/Details.php

<?php
/**
 * Copyright © Magento, Inc. All rights reserved.
 * See COPYING.txt for license details.
 */
namespace Magento\Sales\Block\Adminhtml\Order;

/**
 * Class Details
 * @package Magento\Sales\Block\Adminhtml\Order
 */
class Details extends \Magento\Framework\View\Element\Template
{
    /**
     * @var string
     */
    protected $_template = 'Magento_Sales::order/details.phtml';
}